Ugh. The Kawasaki motor finally died on my zero turn...what really sucks is that it was likely caused by the engine being assembled incorrectly by the factory, but the local distributor made a ridiculous finding which killed any chance of it being fixed under warranty. He claimed that the airbox I made to relocate the air intake away from the grass catcher didn't have enough holes in it, causing the engine to run lean...I checked, there was no noticeable difference in the intake vacuum whether or not the airbox I made was open or closed, or if the whole setup was reverted to stock. Meanwhile, the fan in the engine was installed incorrectly, so it wasn't cooling the engine properly, causing it to overheat. It is unlikely I will buy anything else from Arjay's in Edmonton...
Anyway, I bought a similarly sized Briggs&Stratton engine with the same crankshaft dimensions, mounting points, and harness connection [but of course, you have to separately buy the exhaust, and an 'installer' manual from B&S, and then a separate manual with torque specs, B&S are kings of nickle and diming you to death]. Tomorrow I have to get some tubing to alter the exhaust a bit so it doesn't interfere with the frame of the lawnmower.